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A 12-step total synthesis of the natural product dysiherbol A, a strongly anti-inflammatory and anti-tumor avarane meroterpene isolated from the marine sponge Dysidea sp., was elaborated. As key steps, the synthesis features an enantioselective Cu-catalyzed 1,4-addition/enolate-trapping opening move, an Au-catalyzed double cyclization to build up the tetracyclic core-carbon skeleton, and a late installation of the C5-bridgehead methyl group via proton-induced cyclopropane opening associated with spontaneous cyclic ether formation. The obtained pentacyclic compound (corresponding to an anhydride of the originally suggested structure for dysiherbol A) showed identical spectroscopic data as the natural product, but an opposite molecular rotation. CD-spectroscopic measurements finally confirmed that both the constitution and the absolute configuration of the originally proposed structure of (+)-dysiherbol A need to be revised., (© 2021 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Hypothesis: Foamed surfactant solutions can clean surfaces! We hypothesise that the cleaning efficiency depends on the liquid fraction and on the stability of the foam. We also hypothesise that the cleaning efficiency is the better the smaller the average bubble size is., Experiments: The double syringe technique was used to generate foams with varying liquid fractions but the same, very small bubble sizes with and without perfluorohexane in the gas phase. We performed cleaning tests in which the foams were applied to glass substrates contaminated with a fluorescent oil., Findings: We found that unstable foams clean better than stable foams. Three cleaning mechanisms were identified: (1) imbibition at low liquid fractions, (2) wiping, i.e., shifting of the contact line between oil, foam and glass, at all liquid fractions, and (3) drainage at high liquid fractions. The change of the liquid fraction and of the foam stability lead to different combinations of these mechanisms and thus to different cleaning results., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Background: With the advent of coronavirus disease 2019 (COVID-19), a different perspective on the future of humanity has emerged that emphasizes the importance of building the capacities of healthcare providers in order to assist them with the heavy burden that these changes have placed on them both now and in the future. A reduction in the quality of life and the presence of prolonged fatigue are some of the most imminent problems that emerge among these professionals., Objective: The aim of this study was to determine the effectiveness of a holistic intervention (workshop) for health science students aimed at developing skills that will enable them to obtain a better self-assessment of their quality of life, and prolonged fatigue., Methods: Pre- and post-measures of quality of life, and prolonged fatigue were obtained from 130 health science students, including a group of 96 attendees (cases) of a 4-h wellness workshop and 34 students who did not attend (controls)., Results: Paired t tests indicated a significant improvement in nearly all dimensions related to quality of life, and prolonged fatigue in the case group who attended the workshop., Conclusions: A comprehensive wellness strategy that utilizes a holistic approach can play an important role in improving and promoting essential skills to improve healthcare provider's self-assessment about the quality of life and reduce their prolonged fatigue. The critical importance of these needs has long been recognized, and this will also be crucial for addressing new challenges and emerging realities., Competing Interests: Conflict of InterestThe authors declare no competing interests., (© International Association of Medical Science Educators 2021.)

While adverse conditions in a child's life do not excuse inappropriate behavior, they may cause emotional and behavioral problems that require treatment as a preventive measure to reduce the likelihood of bullying. We aimed to identify differences in the psychosocial profiles of adolescents who classified themselves as bullies, victims, or bully-victims. We performed a cross-sectional study in which data were collected between January 2009 and January 2010 from seven university-based clinics in a large metropolitan area with a predominantly Mexican-American population. We collected data on physical aggression among adolescents who self-categorized into the following groups: uninvolved, bullies, victims, and bully-victims. We determined the psychosocial profiles of the adolescents based on responses to the Youth Self Report (YSR) and parent's responses to the Child Behavior Checklist (CBCL). A one-way analysis of variance and multivariate regression analyses were performed to compare the various components of the psychosocial profiles among the groups. Our analysis of the CBCL and the YSR assessments identified differences between the uninvolved group and one or more of the other groups. No significant differences were observed among the bully, victim, and bully-victim groups based on the CBCL. We did find significant differences among those groups based on the YSR, however. Our results suggest that emotional and behavioral problems exist among bullies, victims, and bully-victims. Therefore, treatment should not focus only on the victims of bullying; treatment is equally important for the other groups (bullies and bully-victims). Failure to adequately treat the underlying problems experienced by all three groups of individuals could allow the problems of bullying to continue.

Carbohydrate- and oligoethylene oxide-based surfactants behave quite differently despite the fact that they are both classes of nonionic surfactants. Intensive studies of a mixture at fixed molar ratio (1:1) of two very common sugar- and oligoethylene oxide-based surfactants, namely n-dodecyl-β-D-maltoside (β-C(12)G(2)) and n-dodecyl hexaethylene oxide (C(12)E(6)), revealed that most properties of the mixture are similar to those of the oligoethylene oxide-based surfactant. In the present work, this mixture is compared to respective "hybrid surfactants". Such hybrid surfactants are surfactants whose head group contains chemically linked carbohydrate and oligoethylene oxide units. In order to study the behaviour of this sort of compounds, we synthesised a new class of surfactants whose head group consists of one carbohydrate-like unit (myo-inositol) and three ethylene oxide units. New regiochemically defined ethoxylated inositol derivatives (referred to as C(12)I(1)E(3) and C(12)E(3)I(1) in the following) were synthesised and studied for their thermotropic and lyotropic liquid crystalline properties as well as for their surface activities. The results are compared with those of the reference systems β-C(12)G(2) and C(12)E(6), and their 1:1 mixture, respectively, and are discussed in terms of structure-property relations., (Copyright © 2011 Elsevier Inc. All rights reserved.)

The photophysical properties of a series of structurally related 4-aminophthalimides and the corresponding 5-aminophthalic hydrazides (luminols) are reported. Absorption, steady-state, and time-resolved fluorescence spectra of luminols exhibited substitution, solvent, and pH dependence. Singlet lifetimes have been determined by time-resolved laser flash spectroscopy. UV spectra in gas phase and DMSO solution were calculated by TD-DFT which revealed the existence of two low-energy excited singlet states with strong pH-sensitivity.

Spatially organized chromophores can be beneficial for advanced applications like for example, organic solar cells, laser technology or non-linear optic devices as well as supramolecular photochemistry. Of particular interest are non-static ordered forms of molecular organization as for example, liquid crystals. With this in mind we synthesised four new regioisomeric isatin derivatives by Suzuki-Miyaura coupling of 4-dodecyloxyphenylboronic acid with all four possible regioisomers of bromoisatin. Liquid crystalline properties are found for 5-(4-dodecyloxyphenyl)isatin, while the other regioisomers do not display a mesomorphic behaviour. The synthesis, physicochemical investigations including polarization microscopy, differential scanning calorimetry and X-ray investigations are discussed and accompanied with density functional theory calculations with respect to the target molecules and their possible H-bonded aggregates. Two distinct setups of supramolecular assemblies for such isatin derivatives are discussed and a model for the mesophase is proposed.

The gas-phase structures of a series of potassiated tertiary amino acids have been systematically investigated using infrared multiple photon dissociation (IRMPD) spectroscopy utilizing light generated by a free electron laser, ion mobility spectrometry (IMS), and computational modeling. The examined analytes comprise a set of five linear N,N-dimethyl amino acids derived from N,N-dimethyl glycine and three cyclic N-methyl amino acids including N-methyl proline. The number of methylene groups in either the alkyl chain of the linear members or in the ring of the cyclic members of the series is gradually varied. The spectra of the cyclic potassiated molecular ions are similar and well resolved, whereas the clear signals in the respective spectra of the linear analytes increasingly overlap with longer alkyl chains. Measured IRMPD spectra are compared to spectra calculated at the B3LYP/6-311++G(2d,2p) level of theory to identify the structures present in the experimental studies. On the basis of these experiments and calculations, all potassiated molecular ions of this series adopt salt bridge structures in the gas phase, involving bidentate coordination of the potassium cation to the carboxylate moiety. The assigned salt bridge structures are predicted to be the global minima on the potential energy surfaces. IMS cross-section measurements of the potassiated systems show a monotonic increase with growing system size, suggesting that the precursor ions adopt the same type of structure and comparisons between experimental and theoretical cross sections are consistent with salt bridge structures and the IRMPD results.

Carbohydrates are interesting starting materials for scientific and industrial syntheses as they allow a versatile chemistry. Moreover, they are of natural origin and environmentally benign. During the past few years, inositol, a rather "exotic" carbohydrate, and its derivatives have gained increasing attention. Here, we describe the syntheses of new regiochemically defined inositol monoethers and monoesters as well as regioisomeric inositol ester mixtures and investigate their amphitropic liquid crystallinity. Furthermore, first results on their surface activity in aqueous solutions are given and compared with classical sugar surfactants.

Dissociation kinetics of the K(+) loss reaction of three potassiated tertiary amino acids (Scheme 1) were studied by infrared multiple photon dissociation (IRMPD) in a Fourier transform ion cyclotron resonance (FT ICR)-MS instrument. The aim of the study was to probe if a kinetic study by IRMPD can yield useful information on the ion structure of the precursor ion species. The measured activation energy values determined by IRMPD are related to the potassium affinity, DeltaH(K(+)), of N-methyl proline determined by threshold collision-induced dissociation experiments. By appropriate scaling with this reference value, the experimentally determined activation energy values for the K(+) loss are transformed into respective potassium affinities, DeltaH(K(+))(IRMPD). These values match the calculated potassium affinity values for salt bridge (SB) structures, DeltaH(K(+))(SB), substantially better than those for canonical structures with a single formal charge site (charge solvation (CS)), thereby allowing structure identification. This conclusion is consistent with other spectroscopic data, which yielded unambiguous evidence of these tertiary amino acids adopting SB structures in the gas phase. This study demonstrates that IRMPD can be applied to determine individual ion structures in the gas phase, given that adequate reference values are available for proper scaling.

A set of new bis-spirofused 1,2,4-trioxanes 4a-d was obtained from the reaction of cyclohexane-1,4-dione with allylic hydroperoxides 2a-d, bearing an additional hydroxy group in the homoallylic position, by diastereoselective photooxygenation of allylic alcohols 1a-d and subsequent BF(3)-catalyzed peroxyacetalization with the diketone. From the reaction of a monoprotected cyclohexane-1,4-dione 5 with the allylic hydroperoxide 6 derived from the singlet oxygenation of methyl hydroxytiglate, one monospiro compound was obtained, the 1,2,4-trioxane ketone 7, as well as a mixture of the diastereoisomeric syn- and anti bis-1,2,4-trioxanes 8. The structures of bis-1,2,4-trioxanes were examined theoretically by DFT methods and compared with X-ray structural data in order to evaluate the preferential trioxane ring conformational orientation.

The solution photochemistry of the ortho allyloxy-substituted benzophenone has been investigated in detail. Product analysis revealed formation of a diastereomeric mixture of dihydrobenzofuran derivatives by cyclization via a short-lived intermediate 1,5-biradical and an unusual acetal by a pseudo-Paternò-Büchi rearrangement. The latter reaction pathway was supported by means of laser flash photolysis, where a long-lived intermediate with a maximum absorption band at 380 nm was observed. Besides, theoretical calculations (TD-DFT) of this UV-transient resulted in a band with maximum intensity at 390 nm showing a good correlation between experimental results and theoretical calculations. For comparison, the meta-substituent substrate was also investigated showing preferred triplet-triplet energy transfer.

Carbohydrates are an attractive class of starting materials for organic syntheses because they are of natural origin, environmentally friendly, and highly functionalized, in this way promoting a sustainable chemistry. A somewhat exotic but nevertheless readily available family of carbohydrates allowing a fascinating chemistry are inositols (cyclohexane-1,2,3,4,5,6-hexols), which we currently use for the synthesis of new surfactants. In our previous work, we reported on the synthesis of a number of new regiochemically defined myo-inositol ethers and esters and studied their surface activity in aqueous solution as well as their ability to form thermotropic liquid crystals. It turned out that the hydrophilicity of the myo-inositol head group alone does not ensure sufficient water solubility of these surfactants. To improve the water solubility, we increased the inositol head group by the introduction of a tri(ethylene oxide) unit. The resulting surfactant is the first representative of a new class of inositol-based surfactants (CiEjIk) that combine the properties of classical sugar surfactants (CnGm) and oligo(ethylene oxide) alkyl ether surfactants (CiEj).

Bimonthly recordings of ultra-low-frequency acceleration ballistocardiograms overa 2 to 7 year period in 73 patients with ischemic heart disease and 50 matched control subjects within the framework of a clinical follow-up were subjected to measurement of IJ amplitude (reflecting force of contraction), IJ velocity (reflecting contractility), and IJ velocity variation coefficient. These repeated measurements were correlated with 24-hour vanillylmandelic acid (VMA) excretion in the urine, arthythemia incidence, heart rate, and clinical outcome in each subject. Moth-to-month variability of the IJ velocity was highly significantly correlated with 24-hour VMA excretionas well as with the likelihood of subsequent myocardial infartion or sudden death. Data on 24 of the patients with ischemic heart disease were available during a two-year period prior to their death from documented myocardial infarction or presumed fatal arrhythmia without a fresh infarction at autopsy. Their records were compared with those made during the same time period on individually matched control subjects and on patients with documented ischemic heart disease who survived the period of study. The mean force of cardiac contraction (IJ amplitude) was consistently lower in the group destined todie early than in the other two groups during the first 18 months. During the 6 monthsprior to death, however, their tracings show a relatively increased force of cardiac contraction and an increased product of force x pulse rate (referred to as the "drive index"), as well as an increase in the incidence of cardiac arrhythmias. None of these late increases was observed during comparable periods of time among surviving patients orcontrol subjuects.